Rotary diesel engine



Jan. 25, 1949. G. F. PIEPER ROTARY DIESEL ENGINE Filed Sept. 20, 1946 4 Sheets-Sheet l INVENTOR GEORGE F. PIEPER AIIV'VTORNEYS 1949- G. F. PIEPER I 2,460,192

ROTARY DIESEL ENGINE Filed Sept. 20, 1946 l'Sheets-Sheet 2 mu Ill/I VENTOR E F.PIEPER Jan. 25, 1949. G. F. PIEPER ROTARY DIESEL ENGINE Filed Sept. 20, 3.946

4 Sheets-Sheet 3 GEORGE F.PIEPER ATTORNEYS Filed Sept. 20, 1946 4 Sheets-Sheet 4 Jan 25, 1949 G. F. PIEPER A JW ROTARY DIESEL ENGINE INVEYNTOR 38 GEORGE F.'P|EPER Patented Jan. 25, 1949 OFFICE ROTARY DIESEL ENGINE George F; Pieper, Milwaukee; Wis. Application September 20, 1946 Seriat-No'.:698,283'

This invention appertainslto rotary Diesel Another salient object of my invention is to provide novel means for arranging the cylinders and the-pistons in the rotor, so that the cylinders will be di'sposed around. the power shaft and substantially tangentially to a circle concentricv to the power shaft, whereby the power thrust will be delivered directl to the rotor at one side of its ax1s.-

A further object of my invention is. to provide es; mes and. is a further advancement. in this art over my prior Patents 2,263,274,. 2,263,275 and I Claim. 1101. 1213 43) Figure: 3 looking in the illustrating the novel arrangement oi the cylinders and pistons in the rotor and the means for auto-- matieal-ly actuatingthe fuel pumps.

Figure 3 is a substantially diametric section through the engine taken on the line 3---3 of novel means for arranging the rotor eccentric in the stator and the pistons in the rotorin such a manner that during movement of the rotor, the.

pistons will be automatically actuated on their compression strokes,

Afurther important object of my invention is to provide; novel. means for delivering airunder.

compression. to. the cylinders for facilitating, first the scavenging of the burnt charges thereinandsecond, the maximum and desired amount of clean. air for the combustion charge.

A still. further object ofrny invention is to pro- Vide novelmeans for delivering atomized fuel at Figure 2 looking inthe direction of the arrows,

Figure/i isa view taken substantially aterightangles to Eigure 3 and on the line 4 4 of. Figure 2 looking in the direction ofthearrowsl Figure 5 is a fragmentary detail sectional view taken substantially on the line 55 of Figure; 4

looking in the direction: of the arrows and. illus trating the exhaust chamber in the stator.

Figure 6- isl a fragmentary detail sectional view taleen substantially on the. line 6-45 of Figure 2 looking: in the direction of the arrows and illus treating the novel means for bringing about the.

varying of the active stroke ofthe feet pumps.

Referring to theidrawings, in detail-,7 wherein similarreference characters design-ate corre sponding parts throughout the several views the lettenE generally indicates my improved rotary Diesel-origina- The engine includes a stator i in which is ci centrically; mounted: the rotor 8-.

The-stator] can be constructed in various manner's: and as illustrated includes arotor chamber 9 and a pump chamber lil The stator can con sist: of an annular outerwall H and a sidedisc end wall? IZPThis end-wall t2= can. bezrigidly fasteneettoktheannular outerwall it in any'suitablethe desired. time to aoylinder loaded with air un- I der high compression, to bring about the efiective.

firing of the fuel mixture.

A- still further important object of my invention is to provideanovelmeans for varying the active stroke of the fuel pumps to-increase-or de-- crease the amountof fuel charge to the cylinders.

With these and. other objects inview the invention consists in the novel construction, ar-

rangement and formation of parts, aswill be hereinafter more specifically described, claimed.

and illustrated in the accompanying drawings, in

which drawings: 7

Figure I is'a side elevational. view of my novel rotary Diesel engine, parts. of the figure being. shown'broken' away and in section to illustrate structural detail. v

Figure 2. is a central. sectionalview through the engine taken substantially onthe line 2-2 .of

way, suchas by machine screws t3. Fastened tothe other sneer. the outerwall H from the end wall If? is an. end. wall; M. anclthis wall: is formed to providethe chamber H3. As shown in Figures 2, 31' and 4 the chamber Ill is eccentrically disposed relative to the chamber 9 and is, separated Y therefrom b a disc platel5. This disc, plate l5' rotates with the rotor 8 as will be later set forthf The/end walls [2. and M carry suitablebearings l6" for rotatablysupporting the power or drive shaft t l The rotor: 8' and the disc l5 are securely fastened to the shaft ii. and also rigidly fastened to the shaft for rotation: therewith is the pumpplate. l8. This pump plate; in is mount ed for rotation within the pump chamber t0.

As previously stated the rotor 8" is eccentrically mounted within the stator l and the chamber: 1 and consequently the rotor only? bearsaga'inst the stator outer wall H; at one point 'lLhe rotor 8 isin the; nature ofv at circularsolidtblockvand this block is provided at; quarters with cylinders l9 and these cylinders: inrefi'ect form chords relativeto the circumference or'periphery direction: of the arrows;

of the rotor and the cylinders extend tangentially relativeto a circle concentric with the axis of the rotor. 7

To facilitate assemblage, the rotor block is cut away at quarters as at 20 and the cylinders |9 communicate with these cut away portions. Fastened securely in the cut away portions are guide sleeves 2| which actually form continuations of the cylinders. These sleeves, however, are of less diameter than the diameter of the cylinders. Reciprocally mounted within each cylinder is a piston 22 and each piston has formed thereon or secured thereto a piston rod 23 which is slidably mounted within its sleeve 2|. The end of each piston rod remote from the piston 22 has a cap 24 carrying antifriction bearings 25. These bearings are preferably arranged in a semicircle and the caps 24 and the bearings carried thereby are normally urged into constant bearing contact with the inner face of the stator outer wall II, by means of relatively heavy expansion springs 26. These springs are coiled about the sleeves 2| and the rods 23 and bear against the caps 24 at the inner ends of the sleeves.

From the description so far, it can be seen that combustion takes place between a piston 22 and the inner wall or head of the cylinder and consequently during the firing of the charge a thrust is exerted on the rotor which is substantially tangential to a circle concentric to the axis of the rotor.

Novel means is provided for supplying an adequate amount of clean fresh air to the cylinders and this means consists of a pump 21. The pump can be fastened to the stator and is shown to be of the rotary impeller type and can be driven by means of a belt 28 from the shaft l1. The outlet 29 of the pump communicates with a conduit pipe 30 which in turn communicates with an inlet port 3| formed in the stator. This air inlet port communicates with the rotor chamber In and hence this chamber is filled with clean fresh air between the periphery of the rotor and the inner face of the outer wall H of the stator. A one way check valve 32 is placed in the port 3| so as to permit the flow of air under pressure into the chamber in but to prevent the back flow of fluid into the pipe 3|].

Adjacent to the inner end of each cylinder I8 is an air inlet port 33. These ports are formed directly in the rotor and each port is controlled by a spring pressed check valve 34. Hence, at appropriate times fresh air can be sucked into the cylinders in quantities adjacent to the inner ends thereof. Each cylinder also has communicating therewith a flared exhaust port 35 and these ports are formed directly in the rotor adjacent to the outer ends of the cylinders. One way check valves 36 are placed in the exhaust ports. These exhaust ports 35 communicate at all times with exhaust ports 31 formed in the disc l and the pump plate I8. The exhaust ports in the pump plate flare outwardly and communicate at certain times with an arcuate exhaust channel 38 formed in the closure plate l4. This closure plate carries an exhaust pipe 39 which communicates with the exhaust channel 38.

It can be seen that annular gasket rings 4|! can be carried by the closure plate l4 and that these rings bear against the pump plate and function to set up a seal between the pump plate and the closure plate l4.

Novel 'means is provided for supplying atom- 4 ized fuel under pressure to the inner ends of the cylinders l9 at the desired times. This means includes an axial longitudinally extending passage-way 4| formed in the shaft H. The outer end of this passage-way communicates with radially extending passage-ways 42 which communicate at all times with a stationary fuel supply ring 43. This ring has its inner face provided with an annular fuel channel 44 with which the radial ways 42 communicate Fuel is constantly supplied to the channel 44 by a conduit tube 45 which leads from any suitable source of supply. The inner end of the axial passage-way 4| has communicating therewith radially extending fuel feed passage-ways 46 and these passage-ways 46 in turn communicate with similar passage-ways 41 formed in the pump plate l8. A pump 48 is provided for each cylinder and consequently there are four pumps 48 mounted on the pump plate I8. The pump plate H3 is bored radially to receive the pumps and the passage-ways 41 in the pump plate communicate with the inner ends of the pumps. Each pump includes a cylinder 49 and a piston 50. A spring pressed check valve 5| controls the flow of fuel into a pump from a passage-way 41.

Each pump piston is normally urged outwardly.

by an expansion coil spring 52 and the outer ends of the pump pistons 50 carry antifriction rollers 53 which are disposed within the pump chamber Hi. The purpose of these rollers will be later set forth.

Operating in conjunction with the pumps are fuel injectors 54 and these injectors are carried by the rotor 8, the plate l5 and the pump plate I8 and there is a fuel injector 54 for each pump and each cylinder. These fuel injectors are of the type commonly used for spraying atomized fuel into the cylinders of Diesel engines and it is to be noted that each pump is provided with a port which communicates with its injector 54. The nozzle of each injector communicates with a passage-way 56 in the rotor which leads to the inner end of its cylinder I9. Briefly, on the out stroke of a fuel pump piston50 fuel will be taken into the pump from the passage-ways 4|, 46, and 41 and on the inward stroke of a pump piston the fuel under high compression will be forced into the injector and thence into an atomized state into a cylinder.

The fuel pumps are operated in proper sequence and at the proper time by a cam shoe 51 which projects into the pump chamber In through the closure wall I 4. As a pump piston passes the cam shoe 51 the rollers 53 will ride against the inclined face of the shoe and a pump piston 50 will be forced inwardly placing the fuel in its cylinder 49 under high compression. The fuel under high compression will in turn be supplied to a fuel injector 54 through the passage-way 55 and the fuel will then be sprayed by the injector into a cylinder 9. As the rollers 53 ride off of the cam shoe 51 the pump spring 52 will forcibly carry the piston 50 outwardly and consequently fuel will be'sucked into the pump cylinder 49 from the passage-way 41. It being understood that the outward movement of a pump piston will create a suction and unseat the check valve 5| to permit the drawing in of the fuel.

If so desired the cam shoe 51 can be adjusted radially inward and outward of the pump chamber l0 so as to regulate the working stroke of the fuel pump pistons 50. By controlling the active stroke of the pump pistons the quantity of fuel taken in by the pumps and then delivered to theinjectors can be controlled. The cam shoe 5'! can be adjusted in difierent manners. This adjustment can either be by a manually controlled mechanism or by an automatically controlled mechanism. In the present instant I have shownv the cam shoe adjustable by an automatic mechanism and in accordance with the speed of rotation of the rotor 8. A governor 58 is provided and this governor is rotated from the engine shaft ll by means of a pulley belt 59. The pulley belt at is trained over a pulley wheel on the shaft ll and over a. pulley wheel 60 on thegovernon-shaft 51. The governor 58 is of the centrifugal Weight type and as the weightsthereof move outwardly by centrifugal force, a collar 62 is actuated back and forth. This collar in turn operates, through the medium of links 63 a lever 6 This lever is rockably mounted intermediate its ends on a pivot pin 65. The inner end of the lever 64 carries a roller 66 which bears at all times against a cam track 5'? formed in the cam shoe El. Contractile coil springs 58 are operatively connected to the shoe and to the stator casing and normally tend to pull the cam shoe outwardly and against the roller {55. Upon the swinging of the lever 64 the roller acting on the cam track tends to force the shoe inwardly and as the roller moves to the deep end of the cam track the spring 68 functions to pull the cam shoe outwardly. If desired the lever 64 can have operatively connected thereto a link 69 which can lead to a hand operating mechanism.

Referring to the operation of the engine, it can be seen (see Figure 2) the piston 23 in the lower left quadrant is being forced inwardly due to the engagement of the cap 24 with the stator outer wall and is completing its compression stroke. The piston 23 in the upper left quadrant is approaching firing position. The piston 23 in the upper right quadrant is in its power stroke. The piston 23 in the lower right quadrant is in position for scavenging and is just starting on its scavenging stroke.

A complete cycle of operation would proceed as follows:

Air enters the air blower 21 and is forced through pipe 30, past check valve 32, through port 3! into the air chamber Ill. As the rotor 8 revolves in a clockwise direction (still referring to Fig. 2) the piston 23 in the lower right hand quadrant is approximately in position for inward movement. At this time air under pressure from the chamber 9 is sweeping through the rotor air port 33 past the check valve 34 into the cylinder iii. The air functions to replace the burnt gases in the chamber and sweeps the burnt gases from the previous charge through the exhaust port 35 into the port 31 and exhaust chamber 38 from whence it finds its way out to the exhaust pipe.

As the rotor advances, this piston is forced into its cylinder I!) by pressure of the stator outer wall H against the piston cap 24. The cylinder is now filled with air, which has been rushing in from the air chamber 9 and the exhaust port 35 will be cut off and the air will be compressed in the cylinder until the advance of the rotor brings this piston into a position similar to the piston in the upper left quadrant, and with the air in the cylinder at its maximum compression, the fuel pump 48 in the pump section of the rotor will be adjacent to the cam shoe'5'l in the stator. Further slight movement of the rotor actuates this fuel pump, as the fuel pump roller head 53 passes over the cam shoe. The actuation of the pump forces the fuel (drawn previously from the passage at in the shaft) under pressure into the;- injector for the cylinder and when pump pressure is released, the injector then sprays the atomized fuel into the cylinder, and-,the chalge under. com:- pression is fired. It can be seen that the quick charge of fuel from the pump, momentarily forces the spring pressed fuel injector rod back, and when pump pressure is released, the spring pressed injector rod forces the fuel out of the restricted injector nozzle into the cylinder.

The power'of the expanding charge caught betweenthe piston and the base of the cylinderv is exerted. against the cylinder base which advances the rotor until the exhaust passage 35 is uncovered by; the piston. head. This brings the pressure in the cylinder below the pressure of the air in the air chamber 9 and fresh air again sweeps into the cylinder. This cycle of operation is continuous as long as fuel is supplied to the pumps.

The engine can be cooled in any preferred way and as illustrated the outer wall ll of the stator is provided with a water jacket It. Water is circulated through the jacket by a water pump ii and the pump can be driven from the pulley belt 59. It can be seen that this belt is also trained over a pulley wheel 12 carried by the shaft of the pump.

Likewise the engine can be lubricated in any preferred way and I have shown oil injector 13 carried by the stator. This injector can be supplied with lubricating oil from an oil line '34 and oil is forced under pressure through the line to the injector. The injector "l3 sprays the pistons and rotor walls as they pass the injector. The shaft H can also be provided with an axial passage-way 15 for the lubricating oil and this passage-way communicates with a lubricating oil ring 16 by radial passage-ways 18. This oil ring is securely fastened to the stator and receives its lubricating oil from a supply line 79. The axial lubricating oil passage-way 15 has communicating therewith passage-ways 8%? which lead to the cylinders for lubricating the lower cylinder walls. The stator can be provided with an oil sump 8! in which is positioned an oil pump 82 and the outlet of this pump can communicate with the oil lines M and it. The pump can be driven from the shaft l'l by a gear 83 and this gear can also be used in conjunction with a starter 84 for initially turning over the engine.

From the foregoing description, it can be seen that I have provided a simple form of rotary Diesel engine in which the power thrust is delivered directly to the rotor.

Changes in details may be made without departing from the spirit or the scope of my invention but what I claim as new is:

In a rotary internal combustion engine of the type having a stator, a rotor eccentrically mounted in said stator with cylinders therein arranged around the axis of the rotor and extending substantially tangentially to a circle concentric With said axis, pistons slidably mounted in said cylinders, and means urging the pistons in said cylinders to a compression position by the outer wall of the stator during a part of the cycle of rotation of the rotor; said rotor having ongagement at one point only with the outer wall of the stator and defining an air chamber between the stator and rotor, means for supplying fresh air in quantities to the chamber, inwardly, opening intake valves communicatin with the inner ends of the cylinders and having communication With the fresh air chamber, whereby upon 7 outward movement of the pistons, fresh air will be sucked into the cylinders, and means for supplying atomized fuel to the cylinders at the appropriate times during rotation of the rotor.

GEORGE F. PIEPER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 272,562 Lenhardt Feb. 20, 1883 580,838 Almond Apr. 20, 1897 931,837 Beach Aug. 24, 1909 15 Number N umber Name Date Ricardo et a1 May 5, 1914 Cole Sept. 28, 1915 Brown Oct. 29, 1918 McDonald May 25, 1920 Lawrence Feb. 9, 1926 Hubbard Oct. 25, 1927 McCann Feb. 12, 1935 FOREIGN PATENTS Country Date Germany Oct. 15, 1908 Great Britain Dec. 15, 1909 Great Britain Apr. 27, 1931 

